A bacterial cell divides once every minute and takes an hour to fill a cup. How much time will it take to fill half the cup ?
(a) 60 minutes
(b) 59 minutes
(c) 30 minutes
(d) 15 minutes

Options

A. 60 minutes
B. 59 minutes
C. 30 minutes
D. 15 minutes

Explanation

To solve the problem of how long it takes for a bacterial cell to fill half a cup, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Doubling Time**: The problem states that a bacterial cell divides every minute. This means that every minute, the number of bacteria doubles.

2. **Determine Full Cup Time**: According to the question, it takes 60 minutes (1 hour) for the bacteria to fill the entire cup.

3. **Analyze the Doubling Process**: If the cup is full at 60 minutes, we can deduce that at 59 minutes, the cup must have been half full. This is because the bacteria double in number every minute. Therefore, if the cup is full at 60 minutes, it must have been half full just one minute earlier.

4. **Conclusion**: Thus, it takes 59 minutes to fill half the cup.

### Final Answer:
(b) 59 minutes

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